#include <iostream>
#include <fstream>

using namespace std;

int n, contuar = 2;
fstream ciurin, ciurout;

int main()
{
    ciurin.open("ciur.in", ios::in);

    ciurin >> n;

    ciurin.close();

    if(n >= 5)
        contuar = 3;
    if(n >= 7)
        contuar = 4;

    for(int i = 3; i <= n; i++)
    {
        if(i % 2 != 0 && i % 3 != 0 && i % 5 != 0 && i % 7 != 0)
        {
            contuar++;
        }
    }

    ciurout.open("ciur.out", ios::out);

    ciurout << contuar;

    ciurout.close();

    return 0;
}